Vulnerability library
Security checkFebruary 13, 2026

Cloudflare Agents is Vulnerable to Reflected Cross-Site Scripting in the AI Playground's OAuth callback handler

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Medium severitynpmagents

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Description

Summary

A Reflected Cross-Site Scripting (XSS) vulnerability was discovered in the AI Playground’s OAuth callback handler. The error_description query parameter was directly interpolated into an HTML script tag without proper escaping, allowing attackers to execute arbitrary JavaScript in the context of the victim’s session.

Recommendation

Update the agents package to the latest compatible version. Followings are version details:

  • Affected version(s): < 0.3.10
  • Patched version(s): 0.3.10

References

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See something that needs correcting? Let us knowUpdated February 13, 2026